6.We have special river birthday parties in the summer.

夏天，我们为这条河举办特殊的生日宴会。

7.Sometimes we go upstream to a favourite backwater, sometimes we have our party at the boathouse,

which a predecessor of ours at the farm built in the meadow hard by the deepest pool for swimming and

diving.

有时，我们溯流而上来到我们喜爱的回水河汊举办;有时在船坞举办。那船坞是农场一位前辈在一块草地上盖的，

草地紧挨着一个专供游泳、跳水的深水池。

语言点:句子结构分析:两个sometimes后面是两个并列关系的主句，由逗号隔开，这种用法比较少见。

8.In a heat wave we choose a midnight birthday party and that is the most exciting of all.

天气炎热时，我们便选择在半夜举办生日聚会，这种聚会是最令人激动的。

语言点:句子结构分析:heat wave的意思是“热浪。”that指代前面的部分。